If your baseline is drifting, it’s often dirty cell lenses rather than the lamp itself. You can dismantle the flow cell to clean or replace these lenses.
| Symptom | Probable Cause | Corrective Action | |---------|----------------|--------------------| | High baseline noise | Air bubbles in cell | Flush with degassed mobile phase or remove cell and rinse. | | Negative peaks | Sample absorbs less than mobile phase at set wavelength | Change wavelength or check mobile phase UV cutoff. | | Lamp fails to ignite | Lamp expired or power supply issue | Check lamp hours; replace D2 lamp. | | No signal at high sensitivity | Flow cell window dirty | Clean cell with 1M HNO₃, then water, then methanol. | | Wavelength error | Stepper motor failure or filter stuck | Run Wavelength Calibration from service menu (qualified personnel only). | shimadzu spd20a user manual
The is a cornerstone of modern high-performance liquid chromatography (HPLC). As a UV/Vis spectrophotometric detector, it is renowned for its sensitivity, dual-wavelength capability, and exceptional noise reduction. However, to truly leverage its power, one must master its documentation: the Shimadzu SPD-20A user manual . If your baseline is drifting, it’s often dirty